Devices for “locking down” or securing individual rooms against intrusion in institutional settings have become increasingly common due to a greater perceived threat of violence against the resident populations. Schools are a prime example of such institutions, and various methods and devices have been proposed to reliably secure school rooms in response to intruder alerts.
One such device and system is disclosed in U.S. Published App. No. 2014/0306466 to Couturier, the entirety of which is incorporated herein by reference. A door blocking plate has a pair of strong, spaced pins that mate with floor sockets adjacent the inside face of a door. If the door normally opens inward, the plate prevents the door from being forced inwardly from the outside. If the door normally opens outward, a bracket on the inside face of the door forms a large slot through which the plate is dropped to engage the floor sockets, with a portion of the plate extending above the bracket to prevent the door from being pulled open from the outside. A specialized tool can also be provided to release the installed plate from outside the door.